中国黄种人与白种人脑颅骨特征差异初探

目的建立利用脑颅骨特征推断黄种人和白种人种族的判别方程,并评价其法医学意义。方法收集141例成年人脑颅骨样本,其中黄种人60例,白种人81例。选取脑颅骨10项特征指标,对125例样本进行测量,运用SPSS16.0软件对指标数据进行t检验和Fisher判别分析,建立判别方程。并使用16例样本对方程的判别正确率进行盲测。结果本文选择的10项脑颅骨特征指标变量均具有显著性种族差异(P0.05);建立了5组单项指标和4组多项指标进行种族推断的判别方程,综合判别率为74.4%~94.4%;随机选取16例样本的盲测结果,正确率为81.3%~100%。结论脑颅骨具有种族差异性,本文建立的判别方程可在黄种人和白种人的种族推断中选用。     

中国黄种人与白种人脑颅骨特征差异初探

目的建立利用脑颅骨特征推断黄种人和白种人种族的判别方程,并评价其法医学意义。方法收集141例成年人脑颅骨样本,其中黄种人60例,白种人81例。选取脑颅骨lO项特征指标,对125例样本进行测量,运用SPSS16．0软件对指标数据进行t检验和Fisher判别分析,建立判别方程。并使用16例样本对方程的判别正确率进行盲测。结果本文选择的10项脑颅骨特征指标变量均具有显著性种族差异（P〈0．05）;建立了5组单项指标和4组多项指标进行种族推断的判别方程,综合判别率为74．4％～94．4％;随机选取16例样本的盲测结果,正确率为81．3％-100％。结论脑颅骨具有种族差异性,本文建立的判别方程可在黄种人和白种人的种族推断中选用。     

中国汉族人颅骨数字模型的性别判别方法

目的利用步进Fisher法建立多元性别判别函数,对西安地区成年人颅骨进行性别判别。方法从颅面数据库中选择西安地区133个（73男,60女）三维颅骨模型,利用计算机软件测量并统计颅骨的12项几何测量指标和2项角度测量指标,利用步进Fisher方法建立多元性别判别函数,并对方程进行回代检验。结果男性的12项几何测量指标均值大于女性,女性的2项角度测量指标均值大于男性,除2项指标（X7和X14）外,其他指标均存在显著性差异（P〈0.01）。由4项指标建立的判别方程,判别率男性为87.5%,女性为86.67%。结论利用计算机软件可以实现完整颅骨和无下颌的颅骨的性别判别。     

成人颅骨宽度的性别判别分析

为用颅骨判定性别提供依据。应用判别分析方法对收集东北地区已知性别成年男性和女性颅骨40具的颅骨宽度10个指标的性别差异进行分析。结果发现,10个指标中有7项性别差异显著(P<0.05),应用判别分析方法获得4个判别函数方程式,其判别率为96.3%～97.5%,本研究为可用颅骨判定性别提供新的依据。     

面颅的种族差异性研究

目的探索面颅在中国黄种人与欧洲白种人种族鉴定方面的差异性。方法通过对150例中国黄种人和欧洲白种人样本(各75例)面颅骨的观测、分析,选取与种族变化关系密切的51项观测指标进行观测,使用SPSS16.0软件对观测数据逐级进行统计学分析、处理,建立判别方程。从研究样本外随机抽取白种人和黄种人各10例标本进行盲测。结果筛选出7项测量结果相对稳定、种族差异较大指标建立全指标、逐步和多指标判别函数方程共5对,综合判别率在73.2%~89.8%。盲测正确率在75%~95%,结果令人满意,说明判别方程稳定、可靠,对种族鉴别的应用性较好。结论本研究所建立的种族判别方程可应用于中国黄种人与欧洲白种人的种族鉴定。     

残碎下颌骨体（PM1～M2）判定性别的研究

目的　建立高度残碎下颌骨性别判定的判别方程。方法　对国内 8个省市的已知确切性别的 16 0具尸骨 (男 10 8例 ,女 5 2例 ,年龄范围 18～ 75岁 )的下颌骨进行研究 ,测量了下颌骨左侧颌体 (PM1～M2 )段的 2 4项测量指标 ,经社会科学软件包 (SPSS)对测量数据分析 ,筛选出性别差异显著的指标。结果　得到残碎下颌骨性别判别方程共计 14组。最高性别判别率男性为 78 7% ,女性为 76 9% ,综合为 73 8%。结论　该方法适用于碎尸、火灾、飞机失事等案事件以及考古中的高度残碎后牙段下颌骨的性别判别。     

先天性额骨异常误诊为骨折1例

1 案 例 某男,17岁,头部被木棒击伤后感头痛、头昏,无呕吐及意识障碍。检查:前额部有5cm×2cm纵向表皮剥脱并皮下出血,触痛明显,神经系统检查阴性。伤后第二天拍头颅X线摄片示:额骨纵向骨折。经治疗临床症状好转出院。基层公安局法医鉴定结论:外伤致额骨骨折属轻伤。该起伤害案于一年后由被告人提出质疑,要求复查。法医检查,头部未见异常;复查伤后第二天所拍的头颅X线片,额骨中央可见一纵行、类似S型之密度减低区。使额骨分成两块,其边缘可见密度增高之硬化缘。重拍颅骨X线片,与原X线片相对照,影像无任何变化,确定为先天性额骨异常(二分额骨)。鉴定结论为轻微伤。     

中国人股骨的性别鉴定

目的建立中国人股骨性别判定的方程。方法测量来自全国14省区的已知生前确切性别180例（男150例,女30例）个体的双侧股骨21项指标。使用统计软件SPSS13．0对获得的股骨测量项目数据,进行同一性别双侧间及不同性别同侧间的t检验,然后采用Fisher判别分析法和Bayes逐步判别分析法,建立股骨性别判定的系列判别函数。结果股骨单一测量指标中男性判别率最高指标为股骨上髁宽,为94．0％,女性判别率最高指标为股骨头周与股骨颈垂直径,为93．3％,总判别方程的判别率为男性98．0％,女性93．3％。结论本研究提供的判别方程式判别准确率较高,适用于中国人股骨的性别判定。     

关于上腭性别差异的研究

利用判别分析的方法,对200例上腭(石膏模型)的11项指标的性别进行性别研究,为用腭判定性别提供了依据,结果发现,有10个指标存在显著意义的性别差异(P<0.05)。应用判别分析方法,获得3个判别函数式,其判别率在64.00%～76.00%,本研究为用腭判定性别提供依据。     

根据颅骨特征推断中国东北地区汉族成年男性眼外形

目的研究颅骨影像学指标与眼外形之间的相关性。方法对101例20~40周岁中国东北地区汉族成年男性,拍摄头面部正面相片和正侧位X线片,对面宽(x1)、上面宽(x2)、两眶宽(x3)、全面高(x4)、上面高(x5)、颅骨最大宽(x6)、额骨最小宽(x7)、眶宽Ⅱ(x8)、前眶间宽(x9)、全颅最大高(x10)、鼻骨最小宽(x11)、眶高(x12)进行测量及统计学分析。结果通过线性回归分析,建立的推定眼内眦间距(y1)、眼外眦间距(y2)的回归方程分别为y1=0.025 x2+0.291 x3-0.011 x7+0.041 x10-0.525(R=0.613,SEE=0.222 cm)、y2=1.703-0.08 x2+0.573 x3-0.142 x4+0.421 x5+0.096 x7-0.256 x8+0.149 x9+0.071 x10(R=0.745,SEE=0.341 cm)。经回代检验,两方程在±1SEE的准确率分别为75.2%和80.2%。结论所建立的眼外形的回归方程具有较高的推定精度,可以用于实际颅骨面貌复原工作。     

Sexual Dimorphism of the Fetal Ilium: A 3D Geometric Morphometric Approach with Multislice Computed Tomography

Adult sexual dimorphism is well established. However, data regarding fetuses are sparse with contradictory results. Our study aimed to look for fetal sexual dimorphism. Multislice computed tomography (MSCT) examinations and three‐dimensional (3D) reconstructions were recorded on 93 fetal iliac bones aged between 21 and 40 weeks of amenorrhea (WA). The collection was divided into two age groups, with a cutoff at 30 WA. The 3D geometric morphometric analysis was based on outline analysis. We used elliptic Fourier analysis (EFA) because of the difficulty of landmark positioning. Step‐by‐step reconstructions allowed a better comprehension of the fine shape details. Principal component analysis (PCA) and linear discriminant analysis (LDA) were performed on the two age groups. Results did not show any difference between male and female shapes, in both age groups. We demonstrate the feasibility of outline analysis for immature shapes, but sexual dimorphism has not been established in our collection.     

Osteometric analysis of sexual dimorphism in the sternal end of the rib in a west African population.

This study, and others, are being carried out in order to establish a Forensic Anthropology databank on age estimation and sex determination of skeletonized remains in Ghana. An osteometric study of sexual dimorphism in the sternal end of the right fourth rib on 346 consecutive coroner's autopsy cases (221 males, 125 females) of known age, sex, and race was conducted. The height and width of the sternal end of the rib were measured in each case. The sample was analyzed in three groups: young (< 30 years), old (> or = 30 years), and total sample (total group). Stepwise discriminant function analysis showed that the accuracy of sex determination varied from 80% in the young and 74% in the old groups to 78% for the total group. Statistical analysis of the results obtained when the functions derived from the study were tested using another batch of ribs showed the functions to be effective and reliable in determining sex. When functions derived from a previous study of American Whites were used to determine sex in our study sample, the vast majority of males were misclassified as females. This is the first time, to our knowledge, that a Black African population has been studied osteometrically to evaluate sexual dimorphism in the sternal end of the fourth rib.     

Sex diagnosis of Chinese skulls using multiple stepwise discriminant function analysis.

Sixty Chinese skulls (30 males and 30 females) from Liaoning Province of the People's Republic of China were used in this study. Forty-one variables on each skull were measured and one group of 14 and a second group of 5 variables were selected from all the variables by applying multiple stepwise regression on a computer. Discriminant equations for the 14 and 5 variables for sex diagnosis have been obtained and these variables are highly significant. The discriminant rate for the group of 5 variables resulted in accurate sex determination in 96.7% of cases. For the group of 14 variables there was 100% success rate.     

Neuropsychological performance of sexual assaulters and pedophiles

Persons who had been arrested for sexual assault were administered the Luria-Nebraska Neuropsychological Battery and the results compared to a group of normal controls. The sexual assaulters performed significantly worse on 7 of the 14 scales of the battery. The data were then broken down into three groups: (1) those who had forcibly assaulted postpubescent victims, (2) those subjects who had sexually molested a prepubescent child, and (3) normal controls. A discriminant analysis correctly classified 68% of the subjects on the basis of their neuropsychological performance alone.     

Sex determination from the talus and calcaneus measurements

Several studies have demonstrated that discriminant function equations used to determine the sex of a skeleton are population-specific. The purpose of the present research was to develop discriminant function equations for sex determination on the basis of 18 variables on the right and left talus and calcaneus in a modern northern Italian sample. The sample consisted of 118 skeletons (62 males and 56 females) from the Frassetto Collection (University of Bologna). The ages of the individuals ranged from 19 to 70 years. The results indicated that metric traits of the talus (in particular) and calcaneus are good indicators of sexual dimorphism. The percentage of correct classification was high (87.9-95.7%). In view of the differences among current Italian populations, we tested the validity of the discriminant function equations in an independent sample of individuals of different origin (northern and southern Italy). The accuracy of classification was high only for the northern Italians. Most southern Italian males were misclassified as females, confirming the population-specificity of discriminant function equations.     

Sexual Dimorphism of the First Rib: A Comparative Approach Using Metric and Geometric Morphometric Analyses

This research investigated the sexual dimorphism of the first human rib using geometric morphometric and metric approaches on a sample of 285 specimens containing European Americans and African Americans from the Hamann‐Todd collection. Metric measurements were investigated for sexual dimorphism and ancestral differences using univariate statistics. Four type II landmarks and 40 sliding semi‐landmarks were placed outlining the dorsal and ventral curvatures of the ribs. Landmark data were processed using Generalized Procrustes Analyses with Procrustes distance sliding, and the subsequent coordinates were investigated for sexual dimorphism and ancestral differences using Procrustes ANOVAs. Both geometric morphometric and metric data were analyzed using cross‐validated discriminant function analyses to test the hypothesis that variables from both approaches can be combined to increase sex classification rate. European Americans had sex correctly classified as high as 88.05% and African Americans as high as 70.86% using a combination of metric and geometric morphometric variables.     

Prognosis of sexual dimorphism with unfused hyoid bone: Artificial intelligence informed decision making with discriminant analysis

Depending on the metric and non-metric skeletal features of various bones, forensic experts proposed diverse sex identification methods. The main focus of the present study is to calculate sexual dimorphism in human unfused or disarticulated hyoid bone and compared it with studies conducted by different researchers. For this study, 293 unfused hyoid bones were accumulated and investigated from 173 male and 120 female cadavers of the northwest Indian population from the age of 15 to 80 years. Initially, discriminant analysis was performed on the dataset to predict sex and to get an idea for the crucial variables for sexual dimorphism. Later, significant variables predicted by the discriminant analysis were used for machine learning approaches to improve accuracy for sex determination. The standard scaler method is used for pre-processing of the data before machine learning analysis and to prevent overfitting and underfitting, 70 % of the whole dataset was utilized in the training of the model and the remaining data were used for testing the model. According to the discriminant analysis, body length (BL) and body height (BH) were found to be highly significant for the sex determination and predicted sex with 75.1 % accuracy. However, implementation of machine learning approaches such as the XG Boost classifier increased the accuracy to 83 % with sensitivity, and specificity scores of 0.81 and 0.84, respectively. Moreover, the ROC-AUC score achieved by the XG Boost classifier is 0.89; indicating machine learning investigation can improve the sex determination accuracy up to the appropriate standard.     

Sexual variation in bucco-lingual dimensions in Turkish dentition

Sexual differences in the human skeleton have been well studied in many populations. Odontometric analysis of the human sexual variation has been less investigated and mostly derived from the dentition of extinct populations. Turkey is situated in a unique location where populations from different regions mixed with each other and created a rich gene pool. One might anticipate that modern Turkish population is composed of genes from the Balkans, Caucasus, Middle East, Iran and further as well as from ancient Romans, Byzantines, Arabs and Asiatic Turks. It is clear that contemporary Turks are a mixture of these extant and extinct people and ideal to consider it a representative study population. The purpose of this study is to analyze dental dimensions and sexual variation in living Turks and develop forensic techniques to identify human remains from the teeth when any other technique is not available or not reliable. The study is composed of Ankara University dental students (50 male and 50 female casts, average age of 21 years). Bucco-lingual breadths from 14 teeth (I1 through M2 of the maxilla and mandible) are taken from the left side and analyzed using the discriminant function statistics. An intraobserver error test did not indicate any statistically significant difference between any two measurements. Results of the study revealed that males exceeded females significantly (P<0.001) in dimensions. Coefficient of variation was most obvious in I1s and I2s of both jaws in both sexes. Stepwise discriminant function statistics suggested that upper C, and lower C and M2 are the most contributory teeth to the function. Additional formulae were calculated for situation in which only one or a fragmented jaw is available for identification. Overall accuracy of sex diagnosis ranged from 73 to 77%. In conclusion this research supports earlier studies that sexual dimorphism is population specific. While dental difference between the sexes in several human populations has been found highly dimorphic, it was not found so in Turks and accuracy of classification remained low at about 77%. The difficulty or the lack of dimorphism comes from male subjects.